Foam earplugs can be produced by extruding a foamable material through a nozzle and shaping the resulting foam extrusion. As the extrusion moves forward away from the nozzle, the extrusion expands for a short distance forward of the nozzle and begins to solidify. The extrusion can be shaped into earplugs in a number of ways. US patent publication 2004/0060567 describes one way of shaping, by moving dies against opposite sides of the extrusion and then moving the dies forwardly with the moving extrusion.
The extrusion can be most easily shaped using dies that form molds, by molding the extrusion while the foam is still expanding and while it has not solidified. However, it usually requires a distance along the extrusion to move the dies against the opposite sides of the extrusion and the extrusion usually has begun or finished solidifying by then. Systems and methods that allow the dies to mold the foam material while the extrusion is still expanding or soon after expansion has stopped, would be of value.